Sheryl Sandberg: Facebook's Billion-Dollar Woman

Sheryl Sandberg is jokingly referred to as the “grown up” at Facebook.

As the social network’s COO, Sandberg runs its all-important advertising business, business development, and oversees hiring. In her four years at the company she’s helped Facebook become profitable, expand internationally, and grow its user base by more than a dozen times over to over 900 million. While her boss, Mark Zuckerberg oversees Facebook’s products, the bottom line is that she figures out how they can make money, without alienating users.

Sandberg’s story is a nice complement to Zuckerberg’s Harvard dropout tale. She graduated from Harvard, first in her major, economics and also graduated from Harvard Business School. Her undergraduate thesis advisor served as a key mentor and boss. He hired her as a researcher at the World Bank soon after she graduated college, and later, he brought her on as his Chief of Staff at the Treasury, where he would become Treasury Secretary.